Direct capture of CO 2 from anthropogenic emissions is an imperative societal task as the concentration of global atmospheric CO 2 continues to increase drastically. The longterm goal of negative emission requires methods to remove carbon directly from the atmosphere, oceanwater, and nonpoint sources. Ionic liquids (ILs) have had a pivotal impact on finding and implementing innovative solutions that enable a more sustainable future. Here, we report the first example of an IL-enabled approach for direct CO 2 capture from the atmosphere on a laboratory scale. These de novo bioderived materials represent an ideal milieu for direct carbon capture applications because of their nonvolatility and a priori low toxicity. Easily prepared liquid salts based on a mixture of three common amino acids, valine, leucine, and isoleucine, were found to be effective sorbents for ready and reversible CO 2 sequestration from air despite its very low concentration. Collectively known as branched-chain amino acid, they are commonly derived from biowaste products, for example, feathers, fur, and even human hair. Therefore, the resultant ILs from the "waste" amino acids provide an exciting prospect in terms of CO 2 transformation and waste utilization. We provided valuable design insights for engineering structure−property relationships in amino acid-based ILs. The impact of moisture on the absorption characteristics and capacity was evaluated in ambient conditions. We postulate that the high capture efficiency and stability of these ILs make them superior to present amine-and alkali-assisted approaches for the direct air capture of CO 2 as a scalable process.

The utility of visible light for 3D printing has increased in recent years owing to its accessibility and reduced materials interactions, such as scattering and absorption/degradation, relative to traditional UV light‐based processes. However, photosystems that react efficiently with visible light often require multiple molecular components and have strong and diverse absorption profiles, increasing the complexity of formulation and printing optimization. Herein, a streamlined method to select and optimize visible light 3D printing conditions is described. First, green light liquid crystal display (LCD) 3D printing using a novel resin is optimized through traditional empirical methods, which involves resin component selection, spectroscopic characterization, time‐intensive 3D printing under several different conditions, and measurements of dimensional accuracy for each printed object. Subsequent analytical quantification of dynamic photon absorption during green light polymerizations unveils relationships to cure depth that enables facile resin and 3D printing optimization using a model that is a modification to the Jacob's equation traditionally used for stereolithographic 3D printing. The approach and model are then validated using a distinct green light‐activated resin for two types of projection‐based 3D printing.

In this work, we investigated the effects of a single covalent link between hydrogen bond donor species on the behavior of deep eutectic solvents (DESs) and shed light on the resulting interactions at molecular scale that influence the overall physical nature of the DES system. We have compared sugar-based DES mixtures, 1:2 choline chloride/glucose [DES(g)] and 1:1 choline chloride/trehalose [DES(t)]. Trehalose is a disaccharide composed of two glucose units that are connected by an α-1,4-glycosidic bond, thus making it an ideal candidate for comparison with glucose containing DES(g). The differential scanning calorimetric analysis of these chemically close DES systems revealed significant difference in their phase transition behavior. The DES(g) exhibited a glass transition temperature of −58 °C and behaved like a fluid at higher temperatures, whereas DES(t) exhibited marginal phase change behavior at −11 °C and no change in the phase behavior at higher temperatures. The simulations revealed that the presence of the glycosidic bond between sugar units in DES(t) hindered free movement of sugar units in trehalose, thus reducing the number of interactions with choline chloride compared to free glucose molecules in DES(g). This was further confirmed using quantum theory of atoms in molecule analysis that involved determination of bond critical points (BCPs) using Laplacian of electron density. The analysis revealed a significantly higher number of BCPs between choline chloride and sugar in DES(g) compared to DES(t). The DES(g) exhibited a higher amount of charge transfer between the choline cation and sugar, and better interaction energy and enthalpy of formation compared to DES(t). This is a result of the ability of free glucose molecules to completely surround choline chloride in DES(g) and form a higher number of interactions. The entropy of formation for DES(t) was slightly higher than that for DES(g), which is a result of fewer interactions between trehalose and choline chloride. In summary, the presence of the glycosidic bond between the sugar units in trehalose limited their movement, thus resulting in fewer interactions with choline chloride. This limited movement in turn diminishes the ability of the hydrogen bond donor to disrupt the molecular packing within the lattice structure of the hydrogen bond acceptor (and vice versa), a crucial factor that lowers the melting point of DES mixtures. This inability to move due to the presence of the glycosidic bond in trehalose significantly influences the physical state of the DES(t) system, making it behave like a semi-solid material, whereas DES(g) behaves like a liquid material at room temperature.